I now have a D700 and was wondering with it being a FX camera if this is something I should look at again.

IMO I'd say no. As someone already mentioned you'd need to use DX crop mode to avoid vignetting, getting you down to 5-6 mp. If you can get past the 5-6 mp you also lose the amazing FF viewfinder and have to frame using the smaller DX overlay.

Since you mentioned sports I don't know if any of the 80-200's would work for you unless you found a used AF-S version. I can't comment on that myself but you can search and find others who have. A used 70-200 VR I or used / new 70-200 VR II may be your best bet. In DX crop mode the 50-150 would provide a field of view similar to 75-225 on FX, if budget is that much of a concern maybe look at Sigma's 70-200 instead of the 50-150 or the Nikkor's.

If you had a D800 that's likely a different story since it's DX crop mode has a pixel count very close to a D7000.

What should I look for to tell if a 70-200 is VR I or VR II? Most of the ones on ebay don't say one way or another or say VR II.